We don't sell the WiFi shield and I don'[t have one here to test with. But according to the board pinouts, there should be no pin conflicts with the camera as you have it wired: http://arduino.cc/en/Main/ArduinoWiFiShield

However, in your second test, you wired the SPI for the SD differently. Try it using Soft-SPI on pins 10-13 as it is on the Wi-Fi card. There may be a library conflict with soft-spi.